Chris Abbott is the founder and executive director of Open Briefing, the world’s first civil-society intelligence agency.

Media coverage of the G20 protests has focused almost entirely on the violence outside the Bank of England and, following the release of Guardian footage, the tragic death of Ian Tomlinson. Events at the Bishopsgate Climate Camp, which was cordoned off in an aggressive operation by riot police, went largely unreported by the BBC and other major media outlets. Most of the reporting has come from online sources (see Stuart White and Beth McGrath for example). Here we publish another eye-witness account of the aggressive police action.

Chris Abbott: I went down to the climate camp after work on Wednesday as I had heard that it was completely peaceful and I wanted to see what it was like. Unfortunately, I got trapped there when the police first charged and then penned everyone in early in the evening and none of us could get out (this was about 7.00-7.30pm). Footage of this is now on YouTube. During this first, entirely unprovoked, attack I lost my girlfriend in the crowd - but I later found out she was punched by a policeman while trying to stop another girl being trampled on after being knocked to the floor.

Once that had calmed down, my girlfriend and I found each other and were sat with others in front of the line of riot police on the south side of Bishopsgate. It was completely peaceful once again and we were even joking and talking with the police. We were there for a couple of hours when they suddenly charged again without any warning (this was about 9.30-10.00pm). We were still sat down and offered no resistance at all. My girlfriend was pressure pointed on the neck (extremely painful), dragged backwards off me and had both her wrists bent behind her back by two policemen who threatened to break them. They dragged her outside the police cordon and then said "what should we do with her now?" before the other said "let's throw her back in", which they did - head first, with her hands behind her back. She landed on the floor and has now got severe bruising on her legs (which we have photos of) and very painful wrists (which we actually thought might be broken).

At the same time, I was punched full in the face by one of the policemen. I was on the floor and absolutely no threat, but he still punched me. I was pulled up and shoved towards the crowd as a group of policemen descended on me, several of them smashing me in the head repeatedly with the sides of their shields. The whole time I had my hands in the air and did not fight back at all, but that didn't stop them. Luckily someone saw what was happening and managed to pull me free from the group of policemen just before they completely surrounded me and cut me off from everyone else. It frightens me to think what they might have done had I not been pulled free. My nose and the side of my head are still very painful, but I was lucky given the damage that they could have caused from hitting me in the head.

Immediately after it happened we saw that the girl we had been sat next to had also been injured and was going into shock. We tried to get her medical attention, but none of us were offered any assistance at all by the police.

We eventually managed to bluff our way out of the police cordon about 11.30pm, just as things were beginning to turn nasty there (the police had by this point brought in dogs). I feel very sorry for the other peaceful demonstrators who were trapped there. I should make it clear that at no point during the 5-6 hours I was there did I see any violence from anyone who was in the camp (there were no 'anarchists' or people smashing things up), it was entirely the police who were violent. I have a feeling that this is going to be the sort of heavy-handed tactics we will witness far more frequently from the police, particularly if we experience the "summer of rage" that the head of the Met's public order branch has predicted.

We gave a brief video statement and our contact details to one of the legal observers at the time, and I have since followed up by email. I will also write to my MP to see what assistance he can give. I would not have been involved in any violent behaviour or in anyway provoked this kind of response from the police. This was an entirely peaceful event up until the police moved in, and the policing tactics used that evening at Bishopsgate were entirely disproportionate and completely counter-productive.

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